Printing machines, particularly rotary printing machines of the web-fed type, require paper feed in predetermined directions and, frequently, it is necessary to turn the paper web. Turning is effected by providing a turning bar over which the paper web is guided, for example to deflect the paper from a horizontal to a vertical path, or the like.
When changing paper or changing production, it is frequently necessary to readjust the position of the turning bars. Turning bars are customarily located on a cross bar or cross rod, and adjustable, therealong, by rotating a hand wheel which drives a spindle, coupled to the turning bar, to then place the turning bar in the desired position. Locating the turning bar requires some skill and adjustment "by feel" until the required positioned of the turning bar has been found, and by checking the resulting printed or supplied material. For example, the position of the turning bar has to be adjusted, in small steps, until a certain folding position or folding operation is properly aligned. Such adjustment "by feel" requires skill and may still result in substantial production of scrap printed material.